about summary refs log tree commit diff stats
path: root/html/apps/mandelbrot-fixed.mu.html
blob: b6781279edd2c3038014a1506db36b6e42112e96 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title>Mu - apps/mandelbrot-fixed.mu</title>
<meta name="Generator" content="Vim/8.1">
<meta name="plugin-version" content="vim8.1_v1">
<meta name="syntax" content="none">
<meta name="settings" content="number_lines,use_css,pre_wrap,no_foldcolumn,expand_tabs,line_ids,prevent_copy=">
<meta name="colorscheme" content="minimal-light">
<style type="text/css">
<!--
pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-color: #ffffd7; }
body { font-size:12pt; font-family: monospace; color: #000000; background-color: #ffffd7; }
a { color:inherit; }
* { font-size:12pt; font-size: 1em; }
.PreProc { color: #c000c0; }
.muRegEdx { color: #af5f00; }
.Special { color: #ff6060; }
.LineNr { }
.muRegEsi { color: #005faf; }
.muRegEbx { color: #5f00ff; }
.Constant { color: #008787; }
.muRegEdi { color: #00af00; }
.muRegEcx { color: #870000; }
.Delimiter { color: #c000c0; }
.muFunction { color: #af5f00; text-decoration: underline; }
.muTest { color: #5f8700; }
.muComment { color: #005faf; }
-->
</style>

<script type='text/javascript'>
<!--

/* function to open any folds containing a jumped-to line before jumping to it */
function JumpToLine()
{
  var lineNum;
  lineNum = window.location.hash;
  lineNum = lineNum.substr(1); /* strip off '#' */

  if (lineNum.indexOf('L') == -1) {
    lineNum = 'L'+lineNum;
  }
  var lineElem = document.getElementById(lineNum);
  /* Always jump to new location even if the line was hidden inside a fold, or
   * we corrected the raw number to a line ID.
   */
  if (lineElem) {
    lineElem.scrollIntoView(true);
  }
  return true;
}
if ('onhashchange' in window) {
  window.onhashchange = JumpToLine;
}

-->
</script>
</head>
<body onload='JumpToLine();'>
<a href='https://github.com/akkartik/mu/blob/main/apps/mandelbrot-fixed.mu'>https://github.com/akkartik/mu/blob/main/apps/mandelbrot-fixed.mu</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr">  1 </span><span class="muComment"># Mandelbrot set using fixed-point numbers.</span>
<span id="L2" class="LineNr">  2 </span><span class="muComment">#</span>
<span id="L3" class="LineNr">  3 </span><span class="muComment"># Install:</span>
<span id="L4" class="LineNr">  4 </span><span class="muComment">#   $ git clone <a href="https://github.com/akkartik/mu">https://github.com/akkartik/mu</a></span>
<span id="L5" class="LineNr">  5 </span><span class="muComment">#   $ cd mu</span>
<span id="L6" class="LineNr">  6 </span><span class="muComment"># Build on Linux:</span>
<span id="L7" class="LineNr">  7 </span><span class="muComment">#   $ ./translate apps/mandelbrot-fixed.mu</span>
<span id="L8" class="LineNr">  8 </span><span class="muComment"># Build on other platforms (slow):</span>
<span id="L9" class="LineNr">  9 </span><span class="muComment">#   $ ./translate_emulated apps/mandelbrot-fixed.mu</span>
<span id="L10" class="LineNr"> 10 </span><span class="muComment"># Run:</span>
<span id="L11" class="LineNr"> 11 </span><span class="muComment">#   $ qemu-system-i386 code.img</span>
<span id="L12" class="LineNr"> 12 </span>
<span id="L13" class="LineNr"> 13 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L13'>main</a></span> <a href='../500fake-screen.mu.html#L14'>screen</a>: (addr <a href='../500fake-screen.mu.html#L14'>screen</a>), keyboard: (addr keyboard), data-disk: (addr disk) <span class="Delimiter">{</span>
<span id="L14" class="LineNr"> 14 </span>  <span class="muComment"># Initially the viewport is centered at 0, 0 in the scene.</span>
<span id="L15" class="LineNr"> 15 </span>  <span class="PreProc">var</span> scene-cx-f: int
<span id="L16" class="LineNr"> 16 </span>  <span class="PreProc">var</span> scene-cy-f: int
<span id="L17" class="LineNr"> 17 </span>  <span class="muComment"># Initially the viewport shows a section of the scene 4 units wide.</span>
<span id="L18" class="LineNr"> 18 </span>  <span class="PreProc">var</span> scene-width-f: int
<span id="L19" class="LineNr"> 19 </span>  copy-to scene-width-f, <span class="Constant">0x400</span>/<span class="Constant">4</span>
<span id="L20" class="LineNr"> 20 </span>  <span class="Delimiter">{</span>
<span id="L21" class="LineNr"> 21 </span>    <a href='mandelbrot-fixed.mu.html#L127'>mandelbrot</a> <a href='../500fake-screen.mu.html#L14'>screen</a> scene-cx-f, scene-cy-f, scene-width-f
<span id="L22" class="LineNr"> 22 </span>    <span class="muComment"># move at an angle slowly towards the edge</span>
<span id="L23" class="LineNr"> 23 </span>    <span class="PreProc">var</span> adj-f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> scene-width-f, <span class="Constant">0x12</span>/<span class="Constant">0</span>.<span class="Constant">07</span>
<span id="L24" class="LineNr"> 24 </span>    subtract-from scene-cx-f, adj-f
<span id="L25" class="LineNr"> 25 </span>    add-to scene-cy-f, adj-f
<span id="L26" class="LineNr"> 26 </span>    <span class="muComment"># slowly shrink the scene width to zoom in</span>
<span id="L27" class="LineNr"> 27 </span>    <span class="PreProc">var</span> tmp-f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> scene-width-f, <span class="Constant">0x80</span>/<span class="Constant">0</span>.<span class="Constant">5</span>
<span id="L28" class="LineNr"> 28 </span>    copy-to scene-width-f, tmp-f
<span id="L29" class="LineNr"> 29 </span>    <span class="PreProc">loop</span>
<span id="L30" class="LineNr"> 30 </span>  <span class="Delimiter">}</span>
<span id="L31" class="LineNr"> 31 </span><span class="Delimiter">}</span>
<span id="L32" class="LineNr"> 32 </span>
<span id="L33" class="LineNr"> 33 </span><span class="muComment"># Since they still look like int types, we'll append a '-f' suffix to variable</span>
<span id="L34" class="LineNr"> 34 </span><span class="muComment"># names to designate fixed-point numbers.</span>
<span id="L35" class="LineNr"> 35 </span>
<span id="L36" class="LineNr"> 36 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a></span> in: int<span class="PreProc"> -&gt; </span>_/eax: int <span class="Delimiter">{</span>
<span id="L37" class="LineNr"> 37 </span>  <span class="PreProc">var</span> result-f/eax: int <span class="Special">&lt;-</span> copy in
<span id="L38" class="LineNr"> 38 </span>  result-f <span class="Special">&lt;-</span> shift-left <span class="Constant">8</span>/fixed-precision
<span id="L39" class="LineNr"> 39 </span>  <span class="Delimiter">{</span>
<span id="L40" class="LineNr"> 40 </span>    <span class="PreProc">break-if-not-overflow</span>
<span id="L41" class="LineNr"> 41 </span>    <a href='../317abort.subx.html#L5'>abort</a> <span class="Constant">&quot;int-to-fixed: overflow&quot;</span>
<span id="L42" class="LineNr"> 42 </span>  <span class="Delimiter">}</span>
<span id="L43" class="LineNr"> 43 </span>  <span class="PreProc">return</span> result-f
<span id="L44" class="LineNr"> 44 </span><span class="Delimiter">}</span>
<span id="L45" class="LineNr"> 45 </span>
<span id="L46" class="LineNr"> 46 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a></span> in-f: int<span class="PreProc"> -&gt; </span>_/eax: int <span class="Delimiter">{</span>
<span id="L47" class="LineNr"> 47 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> copy in-f
<span id="L48" class="LineNr"> 48 </span>  result <span class="Special">&lt;-</span> shift-right-signed <span class="Constant">8</span>/fixed-precision
<span id="L49" class="LineNr"> 49 </span>  <span class="PreProc">return</span> result
<span id="L50" class="LineNr"> 50 </span><span class="Delimiter">}</span>
<span id="L51" class="LineNr"> 51 </span>
<span id="L52" class="LineNr"> 52 </span><span class="muComment"># The process of throwing bits away always adjusts a number towards -infinity.</span>
<span id="L53" class="LineNr"> 53 </span><span class="PreProc">fn</span> <span class="muTest"><a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a></span> <span class="Delimiter">{</span>
<span id="L54" class="LineNr"> 54 </span>  <span class="muComment"># 0</span>
<span id="L55" class="LineNr"> 55 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">0</span>
<span id="L56" class="LineNr"> 56 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L57" class="LineNr"> 57 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">0</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - 0&quot;</span>
<span id="L58" class="LineNr"> 58 </span>  <span class="muComment"># 1</span>
<span id="L59" class="LineNr"> 59 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">1</span>
<span id="L60" class="LineNr"> 60 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L61" class="LineNr"> 61 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">1</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - 1&quot;</span>
<span id="L62" class="LineNr"> 62 </span>  <span class="muComment"># -1</span>
<span id="L63" class="LineNr"> 63 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">-1</span>
<span id="L64" class="LineNr"> 64 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L65" class="LineNr"> 65 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">-1</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - -1&quot;</span>
<span id="L66" class="LineNr"> 66 </span>  <span class="muComment"># 0.5 = 1/2</span>
<span id="L67" class="LineNr"> 67 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">1</span>
<span id="L68" class="LineNr"> 68 </span>  f <span class="Special">&lt;-</span> shift-right-signed <span class="Constant">1</span>
<span id="L69" class="LineNr"> 69 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L70" class="LineNr"> 70 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">0</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - 0.5&quot;</span>
<span id="L71" class="LineNr"> 71 </span>  <span class="muComment"># -0.5 = -1/2</span>
<span id="L72" class="LineNr"> 72 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">-1</span>
<span id="L73" class="LineNr"> 73 </span>  f <span class="Special">&lt;-</span> shift-right-signed <span class="Constant">1</span>
<span id="L74" class="LineNr"> 74 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L75" class="LineNr"> 75 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">-1</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - -0.5&quot;</span>
<span id="L76" class="LineNr"> 76 </span>  <span class="muComment"># 1.5 = 3/2</span>
<span id="L77" class="LineNr"> 77 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">3</span>
<span id="L78" class="LineNr"> 78 </span>  f <span class="Special">&lt;-</span> shift-right-signed <span class="Constant">1</span>
<span id="L79" class="LineNr"> 79 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L80" class="LineNr"> 80 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">1</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - 1.5&quot;</span>
<span id="L81" class="LineNr"> 81 </span>  <span class="muComment"># -1.5 = -3/2</span>
<span id="L82" class="LineNr"> 82 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">-3</span>
<span id="L83" class="LineNr"> 83 </span>  f <span class="Special">&lt;-</span> shift-right-signed <span class="Constant">1</span>
<span id="L84" class="LineNr"> 84 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L85" class="LineNr"> 85 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">-2</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - -1.5&quot;</span>
<span id="L86" class="LineNr"> 86 </span>  <span class="muComment"># 1.25 = 5/4</span>
<span id="L87" class="LineNr"> 87 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">5</span>
<span id="L88" class="LineNr"> 88 </span>  f <span class="Special">&lt;-</span> shift-right-signed <span class="Constant">2</span>
<span id="L89" class="LineNr"> 89 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L90" class="LineNr"> 90 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">1</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - 1.25&quot;</span>
<span id="L91" class="LineNr"> 91 </span>  <span class="muComment"># -1.25 = -5/4</span>
<span id="L92" class="LineNr"> 92 </span>  <span class="PreProc">var</span> f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> <span class="Constant">-5</span>
<span id="L93" class="LineNr"> 93 </span>  f <span class="Special">&lt;-</span> shift-right-signed <span class="Constant">2</span>
<span id="L94" class="LineNr"> 94 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L46'>fixed-to-int</a> f
<span id="L95" class="LineNr"> 95 </span>  <a href='../502test.mu.html#L2'>check-ints-equal</a> result, <span class="Constant">-2</span>, <span class="Constant">&quot;F - <a href='mandelbrot-fixed.mu.html#L53'>test-fixed-conversion</a> - -1.25&quot;</span>
<span id="L96" class="LineNr"> 96 </span><span class="Delimiter">}</span>
<span id="L97" class="LineNr"> 97 </span>
<span id="L98" class="LineNr"> 98 </span><span class="muComment"># special routines for multiplying and dividing fixed-point numbers</span>
<span id="L99" class="LineNr"> 99 </span>
<span id="L100" class="LineNr">100 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a></span> a-f: int, b-f: int<span class="PreProc"> -&gt; </span>_/eax: int <span class="Delimiter">{</span>
<span id="L101" class="LineNr">101 </span>  <span class="PreProc">var</span> result/eax: int <span class="Special">&lt;-</span> copy a-f
<span id="L102" class="LineNr">102 </span>  result <span class="Special">&lt;-</span> multiply b-f
<span id="L103" class="LineNr">103 </span>  <span class="Delimiter">{</span>
<span id="L104" class="LineNr">104 </span>    <span class="PreProc">break-if-not-overflow</span>
<span id="L105" class="LineNr">105 </span>    <a href='../317abort.subx.html#L5'>abort</a> <span class="Constant">&quot;multiply-fixed: overflow&quot;</span>
<span id="L106" class="LineNr">106 </span>  <span class="Delimiter">}</span>
<span id="L107" class="LineNr">107 </span>  result <span class="Special">&lt;-</span> shift-right-signed <span class="Constant">8</span>/fixed-precision
<span id="L108" class="LineNr">108 </span>  <span class="PreProc">return</span> result
<span id="L109" class="LineNr">109 </span><span class="Delimiter">}</span>
<span id="L110" class="LineNr">110 </span>
<span id="L111" class="LineNr">111 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L111'>divide-fixed</a></span> a-f: int, b-f: int<span class="PreProc"> -&gt; </span>_/eax: int <span class="Delimiter">{</span>
<span id="L112" class="LineNr">112 </span>  <span class="PreProc">var</span> result-f/eax: int <span class="Special">&lt;-</span> copy a-f
<span id="L113" class="LineNr">113 </span>  result-f <span class="Special">&lt;-</span> shift-left <span class="Constant">8</span>/fixed-precision
<span id="L114" class="LineNr">114 </span>  <span class="Delimiter">{</span>
<span id="L115" class="LineNr">115 </span>    <span class="PreProc">break-if-not-overflow</span>
<span id="L116" class="LineNr">116 </span>    <a href='../317abort.subx.html#L5'>abort</a> <span class="Constant">&quot;divide-fixed: overflow&quot;</span>
<span id="L117" class="LineNr">117 </span>  <span class="Delimiter">}</span>
<span id="L118" class="LineNr">118 </span>  <span class="PreProc">var</span> dummy-remainder/<span class="muRegEdx">edx</span>: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L119" class="LineNr">119 </span>  result-f, dummy-remainder <span class="Special">&lt;-</span> <a href='../314divide.subx.html#L3'>integer-divide</a> result-f, b-f
<span id="L120" class="LineNr">120 </span>  <span class="PreProc">return</span> result-f
<span id="L121" class="LineNr">121 </span><span class="Delimiter">}</span>
<span id="L122" class="LineNr">122 </span>
<span id="L123" class="LineNr">123 </span><span class="muComment"># multiplying or dividing by an integer can use existing instructions.</span>
<span id="L124" class="LineNr">124 </span>
<span id="L125" class="LineNr">125 </span><span class="muComment"># adding and subtracting two fixed-point numbers can use existing instructions.</span>
<span id="L126" class="LineNr">126 </span>
<span id="L127" class="LineNr">127 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L127'>mandelbrot</a></span> <a href='../500fake-screen.mu.html#L14'>screen</a>: (addr <a href='../500fake-screen.mu.html#L14'>screen</a>), scene-cx-f: int, scene-cy-f: int, scene-width-f: int <span class="Delimiter">{</span>
<span id="L128" class="LineNr">128 </span>  <span class="PreProc">var</span> a/eax: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L129" class="LineNr">129 </span>  <span class="PreProc">var</span> b/<span class="muRegEcx">ecx</span>: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L130" class="LineNr">130 </span>  a, b <span class="Special">&lt;-</span> <a href='../500fake-screen.mu.html#L73'>screen-size</a> <a href='../500fake-screen.mu.html#L14'>screen</a>
<span id="L131" class="LineNr">131 </span>  <span class="PreProc">var</span> width/<span class="muRegEsi">esi</span>: int <span class="Special">&lt;-</span> copy a
<span id="L132" class="LineNr">132 </span>  width <span class="Special">&lt;-</span> shift-left <span class="Constant">3</span>/log2-font-width
<span id="L133" class="LineNr">133 </span>  <span class="PreProc">var</span> height/<span class="muRegEdi">edi</span>: int <span class="Special">&lt;-</span> copy b
<span id="L134" class="LineNr">134 </span>  height <span class="Special">&lt;-</span> shift-left <span class="Constant">4</span>/log2-font-height
<span id="L135" class="LineNr">135 </span>  <span class="PreProc">var</span> y/<span class="muRegEcx">ecx</span>: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L136" class="LineNr">136 </span>  <span class="Delimiter">{</span>
<span id="L137" class="LineNr">137 </span>    compare y, height
<span id="L138" class="LineNr">138 </span>    <span class="PreProc">break-if-&gt;=</span>
<span id="L139" class="LineNr">139 </span>    <span class="PreProc">var</span> imaginary-f/<span class="muRegEbx">ebx</span>: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L237'>viewport-to-imaginary-f</a> y, width, height, scene-cy-f, scene-width-f
<span id="L140" class="LineNr">140 </span>    <span class="PreProc">var</span> x/eax: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L141" class="LineNr">141 </span>    <span class="Delimiter">{</span>
<span id="L142" class="LineNr">142 </span>      compare x, width
<span id="L143" class="LineNr">143 </span>      <span class="PreProc">break-if-&gt;=</span>
<span id="L144" class="LineNr">144 </span>      <span class="PreProc">var</span> real-f/<span class="muRegEdx">edx</span>: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L219'>viewport-to-real-f</a> x, width, scene-cx-f, scene-width-f
<span id="L145" class="LineNr">145 </span>      <span class="PreProc">var</span> iterations/<span class="muRegEsi">esi</span>: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L162'>mandelbrot-iterations-for-point</a> real-f, imaginary-f, <span class="Constant">0x400</span>/max
<span id="L146" class="LineNr">146 </span>      iterations <span class="Special">&lt;-</span> shift-right <span class="Constant">3</span>
<span id="L147" class="LineNr">147 </span>      <span class="PreProc">var</span> color/<span class="muRegEdx">edx</span>: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L148" class="LineNr">148 </span>      <span class="Delimiter">{</span>
<span id="L149" class="LineNr">149 </span>        <span class="PreProc">var</span> dummy/eax: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L150" class="LineNr">150 </span>        dummy, color <span class="Special">&lt;-</span> <a href='../314divide.subx.html#L3'>integer-divide</a> iterations, <span class="Constant">0x18</span>/<span class="Constant">24</span>/size-of-cycle-0
<span id="L151" class="LineNr">151 </span>        color <span class="Special">&lt;-</span> add <span class="Constant">0x20</span>/cycle-0
<span id="L152" class="LineNr">152 </span>      <span class="Delimiter">}</span>
<span id="L153" class="LineNr">153 </span>      <a href='../500fake-screen.mu.html#L557'>pixel</a> <a href='../500fake-screen.mu.html#L14'>screen</a>, x, y, color
<span id="L154" class="LineNr">154 </span>      x <span class="Special">&lt;-</span> increment
<span id="L155" class="LineNr">155 </span>      <span class="PreProc">loop</span>
<span id="L156" class="LineNr">156 </span>    <span class="Delimiter">}</span>
<span id="L157" class="LineNr">157 </span>    y <span class="Special">&lt;-</span> increment
<span id="L158" class="LineNr">158 </span>    <span class="PreProc">loop</span>
<span id="L159" class="LineNr">159 </span>  <span class="Delimiter">}</span>
<span id="L160" class="LineNr">160 </span><span class="Delimiter">}</span>
<span id="L161" class="LineNr">161 </span>
<span id="L162" class="LineNr">162 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L162'>mandelbrot-iterations-for-point</a></span> real-f: int, imaginary-f: int, max: int<span class="PreProc"> -&gt; </span>_/<span class="muRegEsi">esi</span>: int <span class="Delimiter">{</span>
<span id="L163" class="LineNr">163 </span>  <span class="PreProc">var</span> x-f/<span class="muRegEsi">esi</span>: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L164" class="LineNr">164 </span>  <span class="PreProc">var</span> y-f/<span class="muRegEdi">edi</span>: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L165" class="LineNr">165 </span>  <span class="PreProc">var</span> iterations/<span class="muRegEcx">ecx</span>: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L166" class="LineNr">166 </span>  <span class="Delimiter">{</span>
<span id="L167" class="LineNr">167 </span>    <span class="PreProc">var</span> done?/eax: boolean <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L182'>mandelbrot-done?</a> x-f, y-f
<span id="L168" class="LineNr">168 </span>    compare done?, <span class="Constant">0</span>/false
<span id="L169" class="LineNr">169 </span>    <span class="PreProc">break-if-!=</span>
<span id="L170" class="LineNr">170 </span>    compare iterations, max
<span id="L171" class="LineNr">171 </span>    <span class="PreProc">break-if-&gt;=</span>
<span id="L172" class="LineNr">172 </span>    <span class="PreProc">var</span> x2-f/<span class="muRegEdx">edx</span>: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L196'>mandelbrot-x</a> x-f, y-f, real-f
<span id="L173" class="LineNr">173 </span>    <span class="PreProc">var</span> y2-f/<span class="muRegEbx">ebx</span>: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L206'>mandelbrot-y</a> x-f, y-f, imaginary-f
<span id="L174" class="LineNr">174 </span>    x-f <span class="Special">&lt;-</span> copy x2-f
<span id="L175" class="LineNr">175 </span>    y-f <span class="Special">&lt;-</span> copy y2-f
<span id="L176" class="LineNr">176 </span>    iterations <span class="Special">&lt;-</span> increment
<span id="L177" class="LineNr">177 </span>    <span class="PreProc">loop</span>
<span id="L178" class="LineNr">178 </span>  <span class="Delimiter">}</span>
<span id="L179" class="LineNr">179 </span>  <span class="PreProc">return</span> iterations
<span id="L180" class="LineNr">180 </span><span class="Delimiter">}</span>
<span id="L181" class="LineNr">181 </span>
<span id="L182" class="LineNr">182 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L182'>mandelbrot-done?</a></span> x-f: int, y-f: int<span class="PreProc"> -&gt; </span>_/eax: boolean <span class="Delimiter">{</span>
<span id="L183" class="LineNr">183 </span>  <span class="muComment"># x*x + y*y &gt; 4</span>
<span id="L184" class="LineNr">184 </span>  <span class="PreProc">var</span> tmp-f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> x-f, x-f
<span id="L185" class="LineNr">185 </span>  <span class="PreProc">var</span> result-f/<span class="muRegEcx">ecx</span>: int <span class="Special">&lt;-</span> copy tmp-f
<span id="L186" class="LineNr">186 </span>  tmp-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> y-f, y-f
<span id="L187" class="LineNr">187 </span>  result-f <span class="Special">&lt;-</span> add tmp-f
<span id="L188" class="LineNr">188 </span>  compare result-f, <span class="Constant">0x400</span>/<span class="Constant">4</span>
<span id="L189" class="LineNr">189 </span>  <span class="Delimiter">{</span>
<span id="L190" class="LineNr">190 </span>    <span class="PreProc">break-if-&gt;</span>
<span id="L191" class="LineNr">191 </span>    <span class="PreProc">return</span> <span class="Constant">0</span>/false
<span id="L192" class="LineNr">192 </span>  <span class="Delimiter">}</span>
<span id="L193" class="LineNr">193 </span>  <span class="PreProc">return</span> <span class="Constant">1</span>/true
<span id="L194" class="LineNr">194 </span><span class="Delimiter">}</span>
<span id="L195" class="LineNr">195 </span>
<span id="L196" class="LineNr">196 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L196'>mandelbrot-x</a></span> x-f: int, y-f: int, real-f: int<span class="PreProc"> -&gt; </span>_/<span class="muRegEdx">edx</span>: int <span class="Delimiter">{</span>
<span id="L197" class="LineNr">197 </span>  <span class="muComment"># x*x - y*y + real</span>
<span id="L198" class="LineNr">198 </span>  <span class="PreProc">var</span> tmp-f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> x-f, x-f
<span id="L199" class="LineNr">199 </span>  <span class="PreProc">var</span> result-f/<span class="muRegEcx">ecx</span>: int <span class="Special">&lt;-</span> copy tmp-f
<span id="L200" class="LineNr">200 </span>  tmp-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> y-f, y-f
<span id="L201" class="LineNr">201 </span>  result-f <span class="Special">&lt;-</span> subtract tmp-f
<span id="L202" class="LineNr">202 </span>  result-f <span class="Special">&lt;-</span> add real-f
<span id="L203" class="LineNr">203 </span>  <span class="PreProc">return</span> result-f
<span id="L204" class="LineNr">204 </span><span class="Delimiter">}</span>
<span id="L205" class="LineNr">205 </span>
<span id="L206" class="LineNr">206 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L206'>mandelbrot-y</a></span> x-f: int, y-f: int, imaginary-f: int<span class="PreProc"> -&gt; </span>_/<span class="muRegEbx">ebx</span>: int <span class="Delimiter">{</span>
<span id="L207" class="LineNr">207 </span>  <span class="muComment"># 2*x*y + imaginary</span>
<span id="L208" class="LineNr">208 </span>  <span class="PreProc">var</span> result-f/eax: int <span class="Special">&lt;-</span> copy x-f
<span id="L209" class="LineNr">209 </span>  result-f <span class="Special">&lt;-</span> shift-left <span class="Constant">1</span>/log2
<span id="L210" class="LineNr">210 </span>  result-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> result-f, y-f
<span id="L211" class="LineNr">211 </span>  result-f <span class="Special">&lt;-</span> add imaginary-f
<span id="L212" class="LineNr">212 </span>  <span class="PreProc">return</span> result-f
<span id="L213" class="LineNr">213 </span><span class="Delimiter">}</span>
<span id="L214" class="LineNr">214 </span>
<span id="L215" class="LineNr">215 </span><span class="muComment"># Scale (x, y) pixel coordinates to a complex plane where the viewport width</span>
<span id="L216" class="LineNr">216 </span><span class="muComment"># ranges from -2 to +2. Viewport height just follows the viewport's aspect</span>
<span id="L217" class="LineNr">217 </span><span class="muComment"># ratio.</span>
<span id="L218" class="LineNr">218 </span>
<span id="L219" class="LineNr">219 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L219'>viewport-to-real-f</a></span> x: int, width: int, scene-cx-f: int, scene-width-f: int<span class="PreProc"> -&gt; </span>_/<span class="muRegEdx">edx</span>: int <span class="Delimiter">{</span>
<span id="L220" class="LineNr">220 </span>  <span class="muComment"># 0 in the viewport       goes to scene-cx - scene-width/2 </span>
<span id="L221" class="LineNr">221 </span>  <span class="muComment"># width in the viewport   goes to scene-cx + scene-width/2</span>
<span id="L222" class="LineNr">222 </span>  <span class="muComment"># Therefore:</span>
<span id="L223" class="LineNr">223 </span>  <span class="muComment"># x in the viewport       goes to (scene-cx - scene-width/2) + x*scene-width/width</span>
<span id="L224" class="LineNr">224 </span>  <span class="muComment"># At most two numbers being multiplied before a divide, so no risk of overflow.</span>
<span id="L225" class="LineNr">225 </span>  <span class="PreProc">var</span> result-f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> x
<span id="L226" class="LineNr">226 </span>  result-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> result-f, scene-width-f
<span id="L227" class="LineNr">227 </span>  <span class="PreProc">var</span> width-f/<span class="muRegEcx">ecx</span>: int <span class="Special">&lt;-</span> copy width
<span id="L228" class="LineNr">228 </span>  width-f <span class="Special">&lt;-</span> shift-left <span class="Constant">8</span>/fixed-precision
<span id="L229" class="LineNr">229 </span>  result-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L111'>divide-fixed</a> result-f, width-f
<span id="L230" class="LineNr">230 </span>  result-f <span class="Special">&lt;-</span> add scene-cx-f
<span id="L231" class="LineNr">231 </span>  <span class="PreProc">var</span> half-scene-width-f/<span class="muRegEcx">ecx</span>: int <span class="Special">&lt;-</span> copy scene-width-f
<span id="L232" class="LineNr">232 </span>  half-scene-width-f <span class="Special">&lt;-</span> shift-right <span class="Constant">1</span>
<span id="L233" class="LineNr">233 </span>  result-f <span class="Special">&lt;-</span> subtract half-scene-width-f
<span id="L234" class="LineNr">234 </span>  <span class="PreProc">return</span> result-f
<span id="L235" class="LineNr">235 </span><span class="Delimiter">}</span>
<span id="L236" class="LineNr">236 </span>
<span id="L237" class="LineNr">237 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='mandelbrot-fixed.mu.html#L237'>viewport-to-imaginary-f</a></span> y: int, width: int, height: int, scene-cy-f: int, scene-width-f: int<span class="PreProc"> -&gt; </span>_/<span class="muRegEbx">ebx</span>: int <span class="Delimiter">{</span>
<span id="L238" class="LineNr">238 </span>  <span class="muComment"># 0 in the viewport       goes to scene-cy - scene-width/2*height/width</span>
<span id="L239" class="LineNr">239 </span>  <span class="muComment"># height in the viewport  goes to scene-cy + scene-width/2*height/width</span>
<span id="L240" class="LineNr">240 </span>  <span class="muComment"># Therefore:</span>
<span id="L241" class="LineNr">241 </span>  <span class="muComment"># y in the viewport       goes to (scene-cy - scene-width/2*height/width) + y*scene-width/width</span>
<span id="L242" class="LineNr">242 </span>  <span class="muComment">#  scene-cy - scene-width/width * (height/2 + y)</span>
<span id="L243" class="LineNr">243 </span>  <span class="muComment"># At most two numbers being multiplied before a divide, so no risk of overflow.</span>
<span id="L244" class="LineNr">244 </span>  <span class="PreProc">var</span> result-f/eax: int <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L36'>int-to-fixed</a> y
<span id="L245" class="LineNr">245 </span>  result-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> result-f, scene-width-f
<span id="L246" class="LineNr">246 </span>  <span class="PreProc">var</span> width-f/<span class="muRegEcx">ecx</span>: int <span class="Special">&lt;-</span> copy width
<span id="L247" class="LineNr">247 </span>  width-f <span class="Special">&lt;-</span> shift-left <span class="Constant">8</span>/fixed-precision
<span id="L248" class="LineNr">248 </span>  result-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L111'>divide-fixed</a> result-f, width-f
<span id="L249" class="LineNr">249 </span>  result-f <span class="Special">&lt;-</span> add scene-cy-f
<span id="L250" class="LineNr">250 </span>  <span class="PreProc">var</span> second-term-f/<span class="muRegEdx">edx</span>: int <span class="Special">&lt;-</span> copy <span class="Constant">0</span>
<span id="L251" class="LineNr">251 </span>  <span class="Delimiter">{</span>
<span id="L252" class="LineNr">252 </span>    <span class="PreProc">var</span> _second-term-f/eax: int <span class="Special">&lt;-</span> copy scene-width-f
<span id="L253" class="LineNr">253 </span>    _second-term-f <span class="Special">&lt;-</span> shift-right <span class="Constant">1</span>
<span id="L254" class="LineNr">254 </span>    <span class="PreProc">var</span> height-f/<span class="muRegEbx">ebx</span>: int <span class="Special">&lt;-</span> copy height
<span id="L255" class="LineNr">255 </span>    height-f <span class="Special">&lt;-</span> shift-left <span class="Constant">8</span>/fixed-precision
<span id="L256" class="LineNr">256 </span>    _second-term-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L100'>multiply-fixed</a> _second-term-f, height-f
<span id="L257" class="LineNr">257 </span>    _second-term-f <span class="Special">&lt;-</span> <a href='mandelbrot-fixed.mu.html#L111'>divide-fixed</a> _second-term-f, width-f
<span id="L258" class="LineNr">258 </span>    second-term-f <span class="Special">&lt;-</span> copy _second-term-f
<span id="L259" class="LineNr">259 </span>  <span class="Delimiter">}</span>
<span id="L260" class="LineNr">260 </span>  result-f <span class="Special">&lt;-</span> subtract second-term-f
<span id="L261" class="LineNr">261 </span>  <span class="PreProc">return</span> result-f
<span id="L262" class="LineNr">262 </span><span class="Delimiter">}</span>
</pre>
</body>
</html>
<!-- vim: set foldmethod=manual : -->